ohr, Encoding an Organic Hydroperoxide Reductase, Is an In Vivo-Induced Gene inActinobacillus pleuropneumoniae

Publisher Website
Google Scholar
Abstract
Actinobacillus pleuropneumoniaeis the causative agent of porcine pleuropneumonia, a disease characterized by pulmonary necrosis and hemorrhage caused in part by neutrophil degranulation. In an effort to understand the pathogenesis of this disease, we have developed an in vivo expression technology (IVET) system to identify genes that are specifically up-regulated during infection. One of the genes that we have identified as being induced in vivo isohr, encoding organic hydroperoxide reductase, an enzyme that could play a role in detoxification of organic hydroperoxides generated during infection. Among the 12 serotypes ofA.pleuropneumoniae,ohrwas found in only serotypes 1, 9, and 11. This distribution correlated with increased resistance to cumene hydroperoxide, an organic hydroperoxide, but not to hydrogen peroxide or to paraquat, a superoxide generator. Functional assays of Ohr activity demonstrated thatA.pleuropneumoniaeserotype 1 cultures, but not serotype 5 cultures, were able to degrade cumene hydroperoxide. InA.pleuropneumoniaeserotype 1, expression ofohrwas induced by cumene hydroperoxide, but not by either hydrogen peroxide or paraquat. In contrast, anohrgene from serotype 1 cloned intoA.pleuropneumoniaeserotype 5 was not induced by cumene hydroperoxide or by other forms of oxidative stress, suggesting the presence of a serotype-specific positive regulator ofohrinA.pleuropneumoniaeserotype 1.

This publication has 58 references indexed in Scilit: